Nikola,
What what I understand of above - you tried to log out a Jabber phone using Extension Mobility (EM) Logout.
This won't work.
EM doesn't log a phone off , it meanly changes the config ON a phone from user "X" to "no user" (or a default user).
Jabber is not "logged in" to CUCM, its a "registered" phone on CUCM just like a standard hardware phone.
So how do you unregister a normal hardware phone?
You plug it out / switch it off.
Likewise with Jabber - you would have to get the client to exit the Jabber program.
Otherwise Jabber client (software phone) will continue to send keepalive - and be registered to CUCM.
Can you remotely get a program (such as Jabber) on a PC to exit - there are ways - but not sure if this is the best thing to do?
Gerry